/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.catalina.ant;

import org.apache.catalina.Globals;
import org.apache.catalina.startup.Constants;
import org.apache.tomcat.util.descriptor.DigesterFactory;
import org.apache.tomcat.util.digester.Digester;
import org.apache.tools.ant.BuildException;
import org.xml.sax.InputSource;

import java.io.*;

/**
 * Task for validating a web application deployment descriptor, using XML
 * schema validation.
 *
 * @author Remy Maucherat
 * @since 5.0
 */
public class ValidatorTask extends BaseRedirectorHelperTask {


	// ----------------------------------------------------- Instance Variables


	// ------------------------------------------------------------- Properties

	/**
	 * The path to the webapp directory.
	 */
	protected String path = null;

	public String getPath() {
		return (this.path);
	}

	public void setPath(String path) {
		this.path = path;
	}


	// --------------------------------------------------------- Public Methods

	/**
	 * Execute the specified command.  This logic only performs the common
	 * attribute validation required by all subclasses; it does not perform
	 * any functional logic directly.
	 *
	 * @throws BuildException if a validation error occurs
	 */
	@Override
	public void execute() throws BuildException {

		if (path == null) {
			throw new BuildException("Must specify 'path'");
		}

		File file = new File(path, Constants.ApplicationWebXml);
		if ((!file.exists()) || (!file.canRead())) {
			throw new BuildException("Cannot find web.xml");
		}

		// Commons-logging likes having the context classloader set
		ClassLoader oldCL = Thread.currentThread().getContextClassLoader();
		Thread.currentThread().setContextClassLoader
				(ValidatorTask.class.getClassLoader());

		// Called through trusted manager interface. If running under a
		// SecurityManager assume that untrusted applications may be deployed.
		Digester digester = DigesterFactory.newDigester(
				true, true, null, Globals.IS_SECURITY_ENABLED);
		InputStream stream = null;
		try {
			file = file.getCanonicalFile();
			stream = new BufferedInputStream(new FileInputStream(file));
			InputSource is =
					new InputSource(file.toURI().toURL().toExternalForm());
			is.setByteStream(stream);
			digester.parse(is);
			handleOutput("web.xml validated");
		} catch (Exception e) {
			if (isFailOnError()) {
				throw new BuildException("Validation failure", e);
			} else {
				handleErrorOutput("Validation failure: " + e);
			}
		} finally {
			if (stream != null) {
				try {
					stream.close();
				} catch (IOException e) {
					// Ignore
				}
			}
			Thread.currentThread().setContextClassLoader(oldCL);
			closeRedirector();
		}

	}


}
